Dust and aerosol formulations are used as disinfestants in pest control programs. It is an established practice to introduce dust and aerosol insecticides into confined spaces, such as wall voids, ceiling spaces, crawl areas and the like, and also into the atmosphere to control insect infestation. Aerosols are also used for odor control, disinfectants and other purposes. Dusts are also used for other purposes.
Power air dusters are used to dispense insecticide dust. The dusters have motor-driven air pumps and hand-operated nozzles which may be mounted on containers storing the dust. Dip tubes extend into the containers and are used to carry dust to the nozzles. The dust has a tendency to cake and clog the dip tubes or nozzles. The operators shake or rap the nozzles and containers to ensure continuous dust flow. When a nozzle is located in a confined space, it is not feasible to effectively shake the nozzle or container attached thereto. The dusting operation must be stopped to allow the operator to clear out the clogged nozzle and/or dip tube. Liquid materials, such as liquid insecticides and fungicides, are dispensed with applicators operable o direct aerosols to selected locations. An example of a machine used to dispense an aerosol insecticide into the atmosphere is disclosed by Tenney in U.S. Pat. No. 3,917,168. Liquid insecticide is forced from a tank by air pressure to a nozzle. The liquid insecticide is heated in the nozzle and discharged from the nozzle into the atmosphere. Air under pressure is discharged from the nozzle simultaneously with the liquid. The high velocity expanding air and liquid react with each other to break up the liquid into relatively small particles forming an aerosol. This machine is not usable to dispense dust.